Improve formatting of centralized references page after PR #834 merges

[drbenvincent]

Summary

Follow up on the centralized bibliography introduced in PR #834 by improving the rendering of the new References page.

Motivation

PR #834 consolidates per-page bibliography blocks into a single shared docs/source/references.rst page to eliminate duplicate citation warnings during the Sphinx build. That is a sensible cleanup, but it also makes the presentation of the bibliography much more visible to readers.

The bibliography might be easier to scan if entries were formatted more like a conventional APA-style reference list, with surnames first and alphabetical ordering that is visually obvious.

This is not just a markup change inside docs/source/references.rst. The proposed :style: apa7 setting requires an additional pybtex style plugin, so follow-up work will also need to add and install a new docs dependency before the docs build can succeed with APA-style formatting.

This should be treated as follow-up work after PR #834 is merged, since the centralized References page only exists once that PR lands.

Proposed direction

• Evaluate switching the centralized bibliography to an APA-like formatting style so author names render surname-first.
• Consider rendering the bibliography as a bullet list rather than a citation-style list, so labels like [Aba21] are not shown.
• Keep the current author-year inline citation style unless there is a strong reason to change it.

Possible implementation

• Add an APA-compatible pybtex formatting plugin to the docs dependencies, for example pybtex-apa7-style, by updating the docs extras in pyproject.toml.
• Reinstall or refresh the docs environment so the new plugin is available during the Sphinx build.
• Update docs/source/references.rst to use:

.. bibliography::
   :style: apa7
   :list: bullet

• Build the docs and confirm the resulting References page is easier to scan and that inline citations still render acceptably.

Acceptance criteria

• The required APA-style pybtex plugin is added to the docs dependencies and available in the docs build environment.
• The centralized References page is formatted in a more reader-friendly way.
• Entries render surname-first in an APA-like style.
• Labels such as [Aba21] are not shown.
• The page reads as an alphabetized reference list rather than a list of citation labels.
• make html succeeds after the change.

[anevolbap]

Some of the goals listed here are already addressed by PR #834 (now merged):

• Hiding [Aba21] labels: done via the strip_citation_labels Sphinx post-transform (commit a090b83). It removes the <span class="label"> nodes and prepends a bullet marker to each entry.
• Bullet-style rendering: achieved through the post-transform + a CSS hanging indent rule in custom.css. Using :list: bullet directly in the bibliography directive is not viable: sphinxcontrib-bibtex only resolves inline {cite:t}/{cite:p} references from list: citation blocks, so switching list type breaks all inline citations with bibtex.key_not_found warnings.

The remaining open item is APA-style formatting (surname-first, e.g. via pybtex-apa7-style), which would require adding a new docs dependency.